On a clear night there are so many stars in the sky, more than we can probably count. Some stars look brighter than others. If we are really far from cities more stars we can see. These groups of stars are sometimes called constellation. A simple definition of constellation is a cluster of stars in the sky that grouped together in a particular pattern or shape and have been given a name. A more modern astronomical sense of the term is as recognizable pattern of stars whose appearance is associated with mythological characters or creatures or associated earthbound animals or objects. There are 88 official constellations which are recognized by the International Astronomical Union (IAU) which is most reasonable number to deals in billions. Some constellations are only visible in the northern hemisphere while others are only visible in the southern hemisphere. Constellation that are visible in both hemispheres may appear upside down in southern hemisphere. A few constellations can be viewed all year long but most are seasonal and can only be viewed at certain times of the year. The sun is the only known star in our galaxy which is not part of the constellation.
The most famous group of star that is easy to find is Big Dipper (Sapta Rhishi). Most people think of Big Dipper as a constellation itself, but it is an Asterism (Group of familiar stars within a constellation). It is made up of 7 bright stars. Big dipper is a part of constellation Ursa Major and visible all year in the northern hemisphere. Polaris is the brightest star in the constellation of Ursa Major. Orion is another constellation which is character from Greek mythology, a giant hunter who was placed in the stars by Zeus upon his death. The Big Dipper has a peculiar shape and is easy to find, and its more easy following the straight line from the North Star or Polaris, as the two stars on the outside of the bowl shape, point straight towards the Polaris, hence they are also known as the Pointer stars. Finding Polaris can help you find Ursa Minor as well, Polaris is the star at the end of the handle of Ursa minor.
Photo Source : Dan Mitchell (Gettyimages)
Orion, also known as the Hunter, is visible in both hemispheres. The constellation mainly consists of bright blue super-giant stars. The most notable exception being the red super-giant Betelgeuse. Betelgeuse is the largest star in the constellation. It has 1000 times the radius of the sun. The 3 stars which forms a line through Middle of the constellation are as Orion’s Belt. The brightest stars in the constellation is Rigel which is 40,000 times brighter than sun. There is a lot more to Orion than just a few star that is why when astronomers talk about constellation they don’t just mean few stars that might look like something they also mean all others stuff that are part of night sky. Orion is the most easily recognizable constellation.The easiest way to find Orion in the night sky is to look for the belt of Orion, three stars resembling the shape of a bet on the hunter.
Zodiac are group of constellations that forms a circular pattern in the night sky. Zodiac helps astronomers to figure out how other objects travels in the space. At the beginning of the January, the constellations of Sagittarius are highly visible to us on earth. The Greek called Sagittarius the Archer because it looks like a man shooting the arrow. Capricornus is also highly visible in January towards the end of the month. It is sometime called sea goat since it happens to have the head of a goat and the tail of a fish.
Next up in February is Aquarius or the water bearer, a group of ancient people called Babylonians thought that these group of star look like an old man pouring water from a picture.
Moving on to march we can see Pisces or the fishes. Pisces represents Venus, a roman goddess who is said to have turned into a fish, and jumped into a river to escape an evil monster.
Next up in April is Aries. In Greek mythology Aries was a ram with wings. The constellation of Taurus visible in may which look like a bull.
June’s prominent constellation, Gemini is sometime called the twins because it reminded the ancient Greeks of the twin’s son of Zeus.
Cancer which we can see pretty well in July is called the Crab because it reminds some folks.
August constellation is called Leo and looks like a ferocious lion. Seen in
September is Maidens (Virgo) since it looks like a lady holding grain which symbolize the harvest of the Greeks and the remains Libra appears in October when days and night are roughly equal and is considered as symbol of balance.
Scorpius, ‘The scorpion’ is visible in November.
Finishing off the year in late November is Ophiuchus which once called “Serpentarias” because it looks like a man holding serpent or snake. Out of 13 Zodiac constellation 12 of them are used as sign for the zodiac calendar and astrology. The zodiac constellation is located within a band that is about 20’ in the sky.
Photo Source : Google images
This article is contributed by Barsha Singh. Barsa is a student of B.Sc. Biology at Tri-Chandra Multiple Campus, Ghantaghar, Kathmandu